Wire sawing strand and method of making



June 28, 1966 R. F. JOY

WIRE SAWING STRAND AND METHOD OF MAKING Filed Feb. 10, 1961 2 a ask/v6[N6 015 MHC'H/NE R O m V m Robe/*2 [Joy BY WW ATTORNEY United StatesPatent 3,257,792 WIRE SAWING STRAND AND METHOD OF MAKING Robert F. Joy,Bethlehem, Pa., assignor, by mesne assignments, to Bethlehem SteelCorporation, a corporation of Delaware Filed Feb. 10, 1961, Ser. No.88,364 7 Claims. (Cl. 57139) This invention relates to an improved wiresawing strand that is particularly useful for cutting blocks of granite,marble, slate, and other materials.

These strands are usually made by spirally twisting round or irregularlyshaped strips whereby flutes or voids are provided to carry the abrasivematerial that actually does the cutting. customarily, the lay or twistof the strand is reversed at intervals by reversing the direction ofrotation of the stranding machine.

An object of the invention-is to provide a multiple wire strand that haslarge abrasive carrying capacity.

Another object is to provide a strand that affords a large surface toinitially contact the stone to be cut.

Another object is to provide an inexpensive and simple method ofproducing the saw strands.

Other objects will become apparent from the following specification andattached drawing which shows the preferred embodiment of the invention.

FIGURE 1 is an elevational view illustrating a stranding machine and dieset-up embodying the preferred method of producing a 2-wire saw strand;

FIGURE 2 is an enlarged elevation view of a portion of the 2-wire sawstrand, showing the strand before and after shaping according to myinvention;

FIGURE 3 is an enlarged cross-sectional view along line 3-3 of FIGURE 2,of a 2-wire strand that has not been compressed;

FIGURE 4 is an enlarged cross-sectional view, along line 44 of FIGURE 2,of a 2-wire strand that has been compressed.

Similar reference characters refer to similar parts throughout theseveral views of the drawing.

With reference to the drawing, FIGURE 1 illustrates a generaldiagrammatic arrangement of the equipment used to perform easily theobjects of this invention as embodied in a two-wire strand. Two standardround wires 1 and 2 pass from the stranding machine 5, which twists thewires, through a closing die 6 to form a strand 7, a portion of which isshown in FIGURE 2. The strand is passed through straightener rollers 8to equalize the inherent strains from the twisting operation and thenpasses through a round compression die 9 to form the strand 10, aportion of which is shown in FIGURE 2. Addition of compression die 9 isthe only deviation from a normal stranding operation. FIGURE 3 is anenlarged cross-sectional view showing the general shape of the wires 1and 2 after stranding but before passing through the compression die 9.In FIGURE 4, wires 1' and 2' are wires 1 and 2 respectively after theyhave been compressed. It will be seen that wires 1' and 2' have beenflattened to a substantially elliptical shape and that their outersurfaces 11' and 12 have radii corresponding to the radius of thecompression die 9 and larger than the radii of the original round wires1 and 2. These larger outer surfaces afford more area of working contactwhen the strand is initially moved acrossa flat surface of stone and theimproved strand will cut efficiently at the start of the sawingoperation. It will be noted that the flutes or channels 13 and 14between the wires are large relative to the working areas 11' and 12 andafford very good abrasive carrying qualities.

In order to form a two-wire saw strand of .25" diameter, the size usedmost commonly, I prefer to use ice a compression die having a diameterof approximately 93% the diameter of the 2-wire strand. However, thediameter of the die may vary between 88% and 98% of the diameter of thestrand, depending upon the size and number of wires of saw stranddesired.

As an example of my invention, two 0.135" diameter wires were spirallytwisted to form a strand of 0.27" diameter. This strand was thencompressed by a die to form a strand 'of cross-sectional shape shown inFIG- URE 4 and of 0.25" diameter, a reduction of approximately 7%. Thissaw strand was made with the lay or twist being reversed every 25 feetin length, and the lay length, the axial pitch or length of one twist,being about 0.9.

While I have described my invention as embodied in a two-wire strand,the invention is not to be considered as limited to that number ofwires.

I claim:

1. A stone saw comprising two wires spirally twisted to form a strand,each of the wires being of substantially elliptical shape incross-section with a major diameter and a minor diameter, two ends ofsaid minor diameters of said wires being flattened and in contact witheach other along the axis of said strand, each of the other ends of saidminor diameters of said wires forming an outer surface of said strand,said outer .surfaces of each of said wires having a radius equal to theradius of the strand.

2. A stone sawing implement comprising a pair of wires twisted together,each of said wires being substantially ovaliform in cross section, withtheir major axes extending transverse to the longitudinal axis of thepair of wires, the inner peripheries being substantially flat andparallel to the said major axes, the peripheries adjacentthe innerperipheries defining substantial areas for the carrying of water andabrasives.

3. A stone sawing implement comprising two wires only, the wires beingtwisted together longitudinally to form a strand, each of said wireshaving at any cross section thereof a substantially ovaliform shape withits major axis parallel to the major axis of the other, the innermostperipheries of the wires being flat and touching each other throughoutthe length of each inner periphery, the outermost peripheries of saidwires being arcuate and lying on the arc of a common circle, thediameter of said circle being smaller than the sum of two seconddiameters, each of the second diameters being the diameter of a wire ofcircular cross section having the same areas as each of said wires ofthe strand, and the transverse peripheries adjacent the innerperipheries defining a recess of substantial area for carrying water andabrasives.

4. A stone sawing implement comprising two wires only, the wires beingtwisted together longitudinally to form a strand, each of said wireshaving at any cross section thereof a substantially ovaliform shape withits major axis parallel to the major axis of the other, and its minoraxis perpendicular to its major axis, the said ovaliform shape beingsymmetrical about its minor axis, the innermost peripheries of the wiresbeing flat and touching each other throughout the length of each innerperiphery, the outermost peripheries of said wires being arcuate andlying on the arc of a common circle, the diameter of said circle beingsmaller than the sum of two second diameters, each of the seconddiameters being the diameter of a wire of circular cross section havingthe same area as each of said wires of the strand, and the transverseperipheries adjacent the inner peripheries defining a recess ofsubstantial area for carrying water and abrasives.

5. A wire stone sawing strand comprising two wires stranded togetherwith relatively "deep spiral channels er length than said flat portions,the distance from the 10 bottom of each channel taken on a radius fromsaid longitudinal axis to a circle including said circular outerportions being greater than the length of said fiat portions.

6. A method of producing a stone sawing implement comprising the stepsof twisting together a pair of wires of circular cross section to form astrand, and then subjecting the twisted wires of the strand to areshaping operation changing the cross 'sectional shape of each wirefrom a circular shape to a substantially ovaliform shape having the samecross sectional area with the major axes of the reshaped wires extendingin parallel relation to each other across the longitudinal axis of thestrand, the reshaped wires being contiguous with each other,-the

. outer peripheries of said reshaped wires forming cutting surfaces. 7

7. A method of producing a stone sawing implement comprising the stepsof twisting together a pair of wires of circular cross section to form astrand, and then drawing the strand through a circular die, the diameterof which is less than the sum of the diameters of the wires of circularcross section to change the cross sectional shape of each wire from acircular shape to a substantially ovaliform shape having the same crosssectional area such that the major axes'of the reshaped wires extend inparallel relation to each other across the longitudinal axis of thestrand, the reshaped wires being contiguous with each other, the outerperipheries of said reshaped wires forming cutting surfaces, thediameter of said die being such that substantial recessed areasspiralling between the wires are retained.

' References Cited by the Examiner UNITED STATES PATENTS 251,114 12/1881Hallidie 205-162 2,156,652 5/1939 Harris 12521 2,856,914 10/1958Dessureau 12521 2,876,761 3/1959 Stevens 12521 2,884,692 5/1959 Haase etal. 57-156 FOREIGN PATENTS 665,719 1 0/ 1938 Germany.

14,121 8/1891 Great Britain.

MERVIN STEIN, Primary Examiner.

RUSSEL C. MADER, FRANK E. BAILEY, FRAN T. BURROUGH, Examiners.

I. E. PEELE, Assistant Examiner.

1. A STONE SAW COMPRISING TWO WIRES SPIRALLY TWISTED TO FORM A STRAND,EACH OF THE WIRES BEING OF SUBSTANTIALLY ELIPTICAL SHAPE INCROSS-SECTION WITH A MAJOR DIAMETER AND A MINOR DIAMETER, TWO ENDS OFSAID MINOR DIAMETERS OF SAID WIRES BEING FLATTENED AND IN CONTACT WITHEACH OTHER ALONG THE AXIS OF SAID STRAND, EACH OF THE OTHER ENDS OF SAIDMINOR DIAMETERS OF SAID WIRES FORMING AN OUTER SURFACE OF SAID STRAND,SAID OUTER SURFACES OF EACH OF SAID WIRES HAVING A RADIUS EQUAL TO THERADIUS OF THE STRAND.